000
FXUS61 KCLE 261726
AFDCLE
Area Forecast Discussion
National Weather Service Cleveland OH
126 PM EDT Tue Sep 26 2017
.SYNOPSIS...
High pressure over the eastern Great Lakes will weaken today and
tonight. This will allow a cold front to move through the area
Wednesday spreading a cooler, more seasonable air mass across
the area.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
Have made lot`s of minor adjustments to temps. Readings across
the central portion of the area were running a degree or two
Celsius cooler than Monday. In the west they were about the
same and in the east they were warmer. Went ahead and took NW PA
to near 90 even at ERI. Highs at CLE should be a tad cooler
than Monday and elsewhere have nudged temps a degree or two in
either direction given the 14z readings. Have also removed most
of the clouds from the forecast for the next several hours.
Still expect some cumulus later this afternoon.
Previous...The strong upper ridge over the region will weaken
tonight into Wednesday as will the associated surface system.
This will allow a cold front across the nations midsection to
move east across the region Wednesday. Today will be very
similar to the previous several days with highs around 90 and
plenty of sun. Some question as to the chance of rain/thunder on
Wednesday with the MET guidance largely slight chance or below
while the MAV shows a chance pop east, likely for the afternoon
based on frontal timing, and a sight chance west. With the
surface low far north into Canada feel the bulk of the precip
will be outside of the area. Still with dewpoints in the 60s its
hard not to buy into low chance pops east in the afternoon.
Highs Wednesday still above normal but mainly in the 80s.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/...
A more seasonable pattern is expected during the second half of the
work week. Brief high pressure will nudge into the region Wednesday
night through Thursday night, providing mostly dry conditions and
slightly below normal temperatures. Highs on Thursday are only
expected to reach the mid/upper 70s across the region. After lows in
the 50s Wednesday night, lows are expected to drop into the mid 40s
to low 50s across the area Thursday night.
A fairly potent shortwave will drop southeast through the Great
Lakes Friday and Friday night. This may bring a few showers to
portions of the area. There has been two noticeable trends with the
00Z suite of guidance. The first of which is a slightly weaker/more
sheared shortwave moving through the area compared to previous
forecast runs, and second a slightly northward shift in the best
forcing and surface reflection. The 00Z ECMWF and GEM are actually
showing very little precip south and west of a Toledo to Canton
line. However, chances are looking fairly good for precip across
extreme NE OH and NW PA, especially with an added lake contribution
and decent low/mid level lapse rates with the coldest air aloft
tracking over this region. Went ahead with likely pops and a slight
chance of thunder Friday afternoon, with up to 500 j/kg of lake
induced MUCAPE, with a fairly sharp pop gradient to the south and
west. Lingering precip chances will end through the overnight as
much drier air and high pressure filters into the region. Highs on
Friday will remain in the mid/upper 60s across the area.
&&
.LONG TERM /SATURDAY THROUGH MONDAY/...
Quiet long term period expected as high pressure builds across the
region this weekend. After a cool day on Saturday, with highs in the
low to mid 60s, and lows Saturday night in the low/mid 40s, possibly
even upper 30s in favored cool spots around the area, a warming
trend will take place across the area Sunday and Monday. Upper ridge
amplification across the eastern CONUS in response to significant
longwave troughing across the intermountain west will allow for
return flow setup with surface high centered east of the area,
and continuous WAA into the region through even the middle part
of next week. Highs by Monday will return to the low to mid 70s,
a couple of degrees above normal for this time of year.
&&
.AVIATION /18Z Tuesday THROUGH Sunday/...

-- Changed Discussion --

Quiet weather will continue. Just a few cumulus expected this
afternoon with mainly clear skies tonight. Some mid level clouds
will move over NW OH toward daybreak as a front approaches the
area. The front should be close to exiting the area by the end
of the TAF period. Onshore flow will continue at ERI and CLE
this afternoon with light SW flow most other places. Winds will
become W then NW behind the front tomorrow. No precip mention
needed.
OUTLOOK...Non-VFR possible Wednesday afternoon and again on
Friday in sct shra with a small chance of tsra.

-- End Changed Discussion --

&&
.MARINE...
Quiet conditions expected on the lake today and tonight with high
pressure overhead, as winds will be light and variable. A cold front
will push across the lake on Wednesday, with winds increasing out of
the northwest during the day, turning northerly 10-15 kts by
Wednesday night, with a very low end chance for small craft
conditions. Winds will subside to 10 kts or less Thursday as high
pressure build across the region. A stronger front will cross the
lake on Friday with winds increasing out of the northwest, then
north 15-20 kts by Friday night, with a better shot a small craft
conditions. High pressure builds back across the lake Saturday with
winds subsiding and remaining 10 kts or less Saturday night through
Monday.
&&
.CLIMATE...
Upcoming records for Today 9/26:
TOL 92/1998
CAK 89/1900
MFD 87/1998
CLE 91/1998
ERI 89/1998
YNG 89/1934
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...None.
PA...None.
MARINE...None.
&&
$$
SYNOPSIS...TK
NEAR TERM...TK/Kubina
SHORT TERM...Greenawalt
LONG TERM...Greenawalt
AVIATION...Kubina
MARINE...Greenawalt
CLIMATE...